Manufacture of draw-plates or dies.



9 C. HENDERSON MANUFACTURE OF DRAW PLATES 0R (HES.

APPLICATlOH FiLED JUNE 5, I917- Patented Oct. 16, 1917.

JOHN C. HENDERSON, OF WASHINGTON, DISTRICT OF COLUMBIA.

MANUFACTURE OF DRAW-PLATES R DIES.

Specification of Letters Patent.

Patented Oct. to, ram.

Application filed June 5, 1917. Serial No. 172,963.

To all whom it may concern:

Be it known that 1, JOHN C. HENDERSON,

'a citizen of the United States, residing in or Dies, of which the following is a specification.

-My invention relates to the manufacture of dies or die plates for drawing wire and the like; and. it consists in casting molten metal by compression in a permanent metal mold, which mold may be chilled by the agency of an external medium such as water or air that is caused to pass through conduits in the molding members for the express purpose of rapidly extracting heat from the mold and the molten metal under pressure, so as to give it a set, although the metal mold itself may be relied upon to do this without the assistance of some external heat extracting source. After the molded or formed die or draw plate has re- .ceived its set, it is still further chilled by being rapidly immersed in a liquid bath of water or other chilling fluid to fix the homogeneity of the structure and the changed molecular condition of the metal of the die or plate in passing from a molten state'to a solid homogeneous structure, whereby there is produced a metal die or plate having all of the characteristics of hardened tool steel.

The particular object of my invention is to chill every portion of the blank forming the die or draw plate throughout the whole of the mass cast. I have found by experiment that this chilling can not be removed even when the chilled die or draw plate is brought to a red heat during working conditions.

Prior structures of this class only have had the outer surface chilled, that is, the

skin. Accordingly when this chilled skin was removed by perforating the blank to form thecye of the die or draw plate the metal was comparatively soft, hence the whole object of chilling was defeated, and the article rendered useless for the purpose for which it was manufactured.

Vith my invention the chilled pressure cast homogeneous die blank can only be perforated in a satisfactory manner to form the eye of the die or draw plate for w re drawing purposes by the use of a steel point and diamond dust aided by the use of a ina bricant as diamond dies are drilled at the present. And further, I produce an article of manufacture that answers the purposes of the well known dies or draw plates made at the present time by the use of precious stones, and hardened steels and their alloys, which device is exceedingly cheap to manufacture and gives very satisfactory production or manufacturing results.

My present invention will be more fully understood from the accompanying drawing illustrating the means of producing the die or draw plate blank.

Figure l is a view of the male and female mold in partial section containing a batch of metal to be pressure cast.

Fig. 2 is a perspective view of the die or draw plate blank before it is perforated.

Fig. 3 is a partial vertical section of the die or draw plate showing the eye or perforation therein.

lteferring now to the drawing, 1 1s a female member of a metal mold of large mass having an opening 2 for the reception of the plastic metal 3, and 4 is a plunger for pressing the metal into the opening 2 of the member 1 to form a blank to he used as a die or draw plate. The object of making the member 1 of large mass is to effect chilling, although some external medium may also be used for this purpose.

In Fig. 2- the formed and chilled blank 3 is illustrated after it has been properly formed and treated, while in Fig. 3 the blank 3 is shown with a perforation or eye This is the condition of the die when ready for use in the drawing of wire.

In the production of a blank for a wire drawing die or draw plate, I commence by placing a batch of molten metal 3 in the opening 2 of the mold 1 and then press it into shape by the plunger by the aid of hydraulic or other pressure. The mass of the female mold member chills the blank and gives it the'set which changes the properties of the metal cast, in other words, the chemical constituem'sy of the cast iron is changed so that it has properties similar to hardened steel. If the first chilling is deemed .in.-a1lli -ient, a further chilling is caused by immersing in a fluid bath or other external means. After this procedure is gone through the die or draw plate is perforated.

in accordance with the provisions of the patent statutes, I have described the pr1nc1- ple operatinn of my invention, together with 'the articka which new censider t0 represent the best embodiment theraop but I desire to have it understocrd that 'ticie snown is i'nerely illustrativa, and *bhmi the invention can be cmriecl out by other equivalgnt means contemplated within the scope of ihe claims.

Having thus dsscribed my iIl'VDbiO'il 1 01mm:

'1. As a. new whale of manufi'actuw,

of compressed iron cast draw plate blank entne mass under ghiiled tinoughout it" pressure.

As a, new article of n pressum cast (11 v plum blank of scam pressed iron (v its entire chilling manufacture,

pressed iron china hrougheui wheie of i'Ls molecu inr strucpufe.

As a new article cf manufacture a molded draw plate or die :z'aia nli of c0mpi'essefl iron double chiflaai throughsut the Whale 0f its moiecular' structura 5.13.55 A new article 03? mzmu 1110151061 draw plate 0 (ii Mania 9%? cam-- pms' eii iron havin due lactate, e constimenc 0f cast iron and the propertes hardened sta 6. As new amide of manufacture, dmw plate 0 (do blank 05 c01n- 7 iron having ifhg chemical constitu- T cast iron am? the physical propel- 'xnerl steel. 

